The present invention relates to a method and apparatus for controlling a dual clutch transmission (DCT), and more particularly, to a method and apparatus for controlling a DCT, which is capable of fixing a mechanical stuck problem occurring in a clutch of the DCT and helping a vehicle to be normally operated.
DCT refers to a transmission system which has the efficiency of a manual transmission and the convenience of an automatic transmission. The DCT can rapidly shift gears using two clutches (first and second clutches).
The reason why the DCT is getting the spotlight is that the DCT has various advantages.
First, the DCT has the efficiency of a manual transmission.
That is, the DCT has a simpler structure than a conventional automatic transmission which uses a complex planetary gear set. Since power is directly transmitted through the clutches, the DCT has higher efficiency than an automatic transmission which uses fluid transport of a torque converter.
Second, the DCT can continuously transmit power.
That is, since the DCT shifts gears while alternately using two clutches, the power is hardly interrupted even when the DCT shifts gears.
For example, odd gears such as first, third, and fifth gears are connected to the first clutch, and even gears such as second, fourth, and sixth gears are connected to the second clutch.
When a vehicle includes only one clutch, only a third gear is engaged in case where a driver shifts into the third gear. In the DCT, however, second and fourth gears corresponding to the upper and lower gears of the third gear are engaged in a standby state. Thus, when a driver shifts into the second or fourth gear from the third gear, the second or fourth gear is immediately engaged. Therefore, the gear shifting can be smoothly and rapidly performed.
Due to such an advantage, the DCT has been developed and mass-produced by various makers such as Porsche and Volkswagen.
The related art of the present invention is disclosed in Korean Patent Laid-open Publication No. 2012-0077737 published on Oct. 7, 2012 and entitled “Method and apparatus for controlling DCT for vehicle”).
The DCT includes a variety of parts connected therein, and a failure may occur in the connections between the respective parts due to various causes.
When a clutch is stuck, normal gear shifting cannot be performed. Thus, when a clutch is stuck, the conventional DCT enters a limp home mode in which the DCT disables the stuck clutch and performs gear shifting only through the other clutch.
However, when the DCT enters the limp home mode in case where a clutch for engaging the reverse gear is stuck, the vehicle cannot be backed. In this case, a driver may be exposed to a dangerous situation. Furthermore, operation to an auto repair shop which is the purpose of the limp home mode is impossible.